Although cognitive function decreases with age, substantial heterogeneity exists at each age. The most frequently identified determinant of cognitive decline in later life is educational attainment, though the interpretation of this association is complicated by ambiguity as to what education represents. This decline may be attributable to an underlying socioeconomic status gradient, as observed with other aspects of health. Or, it may be interpreted as relating specifically to the process and consequences of education itself (e.g., reserve brain capacity or mental stimulation over the life course). Using wave I and a five year follow-up (wave 3) of the Asset and Health Dynamics Among the Oldest Old study, this research will examine the effects of education and other sociodemographic factors on change in cognitive status, attempting to clarify the extent to which that association is direct and the extent to which it is due to economic confounding. Specifically, using data from this large cohort of persons 70 years and older, this research will: 1) Develop a common metric for component and composite measures of cognitive decline using a regression-based approach to create standardized change scores. Adjusting for normal decline, regression-to-the-mean and familiarity with the test, this method for quantifying change will be applied to the composite measure and the three domains of cognitive status (memory; working memory; knowledge, language and orientation). 2) Delineate the relative contributions of education and other SES covariates to cognitive decline, contrast with baseline cognitive functioning, and conduct comparative analyses by race/ethnic and gender groups. 3) Examine SES-related life course determinants of cognitive decline, such as healthful lifestyle, occupational history, marital status and spouse's education. The ability to test the independent contributions of education and other sociodemographic factors to cognitive decline has been limited by a paucity of survey data that incorporate adequate cognitive status.